Other matching problems have IP implementations in the literature. Kwanashie and Manlove [1]} formulated an IP formulation for the Hospital/Residents problem with ties. Hospital/Residents problem with ties is an extension of the stable marriage problem with ties, where many agents in one group (residents) are matched to one agent in the other group (hospitals). When evaluated on instances with up to 400 residents, the median runtime stayed low, although the mean runtime for the biggest instances was above 300 s. This seems to indicate most instances were easy with a few difficult ones. Podhradsky [2]} created a linear programming formulation for approximating Stable Marriage with ties and incomplete lists, which is NP-hard.
